Baked data 'not exact since frame -1'
You could answer the question if you should &quot;just ignore that message&quot; by yourself: Does the simulation / render looks as expected or at least is the result good enough for what you're looking for? Then ignore the message.
Apart from that, the Blender Reference Manual says the following about baking in frame ranges and offsets (this is in the Fluid section, not general), which suggests baking from frame 1 on and use the offset afterwards: